You will first need to download the file.http://www.tamasoft.co.jp/craft/popupcard_en/download-eng.html
is where you can grab your very own copy. Just click the link in purple shown in the picture above. the installer will guide you through the process. This program is only the free version and does not contain anything but cubes.If you have extra money, you can get the full version from their website.
If a Pop Up Comes up saying that a folder is not created and asks if it needs to be created, Just click okay and continue with the installer.